Detergent compositions containing n-oxide-aminocarboxylates

ABSTRACT

BUILT SYNTHETC ORGANIC DETERGENT COMPOSITIONS COMPRISE OXIDED OF AMINOCARBOXYLATES OR AMINOCARBOXYLIC ACIDS OF THE FORMULA:   (R1-CH(-OH)-CH2-N(-R2)(=O)-R2-COO-)N-X   WHEREIN R1 IS AN ALIPHATIC HYDROCARBON RADICAL OF 4 TO 20 CARBON ATOMS, R2 IS A HYDROCARBON RADICAL OF 1 TO 7 CARBON ATOMS OR IS R3COOXM, R3 IS A DIVALENT ALIPHTIC OR AROMATIC HYDROCARBON RADICAL OF 1 TO 9 CARBON ATOMS, WHICH MAY BE THE SAME AS OR DIFFERENT FROM ANY OTHER R3 RADICAL IN THE COMPOUND, X IS HYDROGEN, ALKALI METAL, ALKALINE EARTH METAL, OTHER SUITABLE SALT-FORMING METAL, AMONIUM, ALKYLAMINE OR ALKANOLAMINE, WHICH MAY BE THE SAME AS OR DIFFERENT FROM ANY OTHER X IN THE FORMULA, M IS FROM 1/3 TO 1 AND N IS FROM 1 TO 3, BOTH M AND N BEING DEPENDENT ON THE VALENCE(S) OF X. IN ADDITION TO THE AMINOCARBOXYLATE, SUCH COMPOSITIONS COMPRISE AN INORGANC BUILDER SALT, SUCH AS SODIUM TRIPOLYPHOSPHATE OR POTASSIUM PYROPHOSPHATE, AND ALSO MAY INCLUDE OTHER ADJUVANT MATERIALS, SUCH AS TRISODIUM NITRILOTRIACETATE, ENZYMES, ANTI-REDESPOSITION AGENTS, BLEACHES OR BLUING AGENTS, GERMICIDES, HYDROTROPES, AUXILIARY DETERGENTS AND SOFTENING AGENTS, ETC. USUALLY, THE AMINOCARBOXYLATE COMPRISES FOR 3 TO 30% OF THE COMPOSITION AND THE INORGANIC BUILDER IS FROM 10 TO 70% THEREOF. THE PRODUCTS MADE MAY BE IN LIQUID OR SOLID FORM, AND ARE PREFERABLY EMPOLYED AS LIQUIDS OR POWDERS. THEY MAY BE UTILIZED AS WASHING-SOFTENING AGENTS IN LAUDERING OR MAY BE EMPLOYED IN PRE-SOAKING OR AFTER-SOAKING OF LAUNDRY, TO IMPROVE THE SOFTENING OF THE WASHED MATERIAL. IN SOME INSTANCES, THE AMINOCARBOXYLATE MAY BE USED WITHOUT INORGANIC BUILDER SALT, IN WHICH CASES IT NORMALLY FUNCTIONS PRIMARILY AS A SOFTENING AGENT AND IS PREFERABLY UTILIZED AFTER COMPLETION OF WASHING.

United States Patent Office 3,700,607 Patented Oct. 24, 1972 N.Y. No Drawing. Filed Nov. 28, 1969, Ser. No. 880,977 Int. Cl. Clld 1/84 US. Cl. 252-527 21 Claims ABSTRACT OF THE DISCLOSURE Built synthetic organic detergent compositions comprise oxides of aminocarboxylates or aminocarboxylie acids of the formula:

wherein R is an aliphatic hydrocarbon radical of 4 to 20 carbon atoms, R is a hydrocarbon radical of 1 to 7 carbon atoms or is R COOX R is a divalent aliphatic or aromatic hydrocarbon radical of 1 to 9 carbon atoms, which may be the same as or different from any other R radical in the compound, X is hydrogen,alkali metal, alkaline earth metal, other suitable salt-forming metal, ammonium, alkylamine or alkanolamine, which may be the same as or different from any other X in the formula, m is from /3 to 1 and n is from 1 to 3, both m and n being dependent on the valence(s) of X. In addition to the aminocarboxylate, such compositions comprise an inorganic builder salt, such as sodium tripolyphosphate or potassium pyrophosphate, and also may include other adjuvant materials, such as trisodium nitrilotriacetate, enzymes, anti-rede'position agents, bleaches or bluing agents, germicides, hydrotropes, auxiliary detergents and softening agents, etc. Usually, the aminocarboxylate comprises from 3 to 30% of the composition and the inorganic builder is from 10 to 70% thereof.

The products made may be in liquid or solid form, and are preferably employed as liquids or powders. They may be utilized as washing-softening agents in laundering or may be employed in pre-soaking or after-soaking of laundry, to improve the softening of the washed material.

'In some instances, the aminocarboxylate may be used without inorganic builder salt, in which cases it normally functions primarily as a softening agent and is preferably utilized after completion of washing.

This invention relates to compositions and processes for the treatment of textiles, clothing or laundry to clean and soften them and to impart anti-static properties to them. The invented compositions and processes incorporate or utilize N-oxide-amino-carboxylates and are particularly adaptable to treatments of cotton and cotton-containing -materials, although they are useful for application to other natural and synthetic materials, too.

-In recent years much research has been undertaken in an attempt to improve the physical properties of washed materials. It has been a principal object of such research to improve the whiteness of the materials being washed, by better removal of soil and stains. To this end, improved cleaning agents, builders, antiredeposition agents, enzymes, for stain removal, brighteners, and bleaches have been employed, sometimes as separate treatments and other times incorporated with the principal detersive agent. Although it is recognized that the primary function of a detergent must be to clean, the substanattainment of this objective has caused industry I erally of the controlled foaming type, resulting in a visible scientists to explore other research areas, inan attempt: to improve further other qualities of their products. flhus, it had been found that laundry, such as cotton clothing articles, when washed with built synthetic organic detergents and air dried, sometimes developed a roughness that made the clothing scratchy to the wearers'skin. To counteract this effect, which also has been noted as a result of washing clothing or other items, such as diapers, with soap or unbuilt synthetic detergents, softening agents have been produced, which are usually added to the-rinse water, after completion of machine washing. Research has been conducted to discover and develop improved softeners and. to obtain such materials'which' mightbe employed in a detergent composition itself, so thatthey would not have to be added in a special operation, after completion of washing. v l Another area of research, especially with respect to synthetic fabrics, such as those made from nylons, polyesters and polyvinyl halides, has been prevention of annoying static charge build-up on textiles. It hasbeen found that by applying certain anti-static chemicals to the textiles, electric charges thereon and the annoying shock to a wearer or one who contacts such material willbe diminished. I v The present invented processes and compositions,'utilizing the N-oxide-aminocarboxylates described herein allow improved washing of textiles and laundry, with the washed materials being of greater softness and having anti-static properties. Such results are obtainable by applying the mentioned compounds, either in built or unbuilt compositions, to the material to be treated, either before, during or after washing. It appears that the N- oxideaaminocarboxylates are exceptionally substantive to fabrics and a sufiicient proportion thereof remains on a fabric so as to make it soft and in many cases, to impart an anti-static effect. This action is especially surprising because the active ingredients themselves are detergents and serve to remove materials from substrates, rather than to deposit them thereon.

Other advantages of the present compositions and methods include their usefulness in hard and soft waters, and at high and low washing temperatures. Thus, surprisingly, it has been found that eflfective detergency, softness and anti-static properties are obtained under such conditions. Furthermore, the compounds are genfoam which is not clogging" in a automatic washing machine. The processes may be used in conjunction with many other treatments of textiles or laundry and'the compositions may be modified to include other detergents and adjuvants, without interfering 'with the desirable activities thereof.

In accordance with the present invention, built synthetic organic detergent compositions comprise an inorganic builder salt and an oxide of an aminocarboxylate or aminocarboxylic acid of the formula:

wherein R is an aliphatic hydrocarbon radical of 4 to 20 carbon atoms, R is an aliphatic or aromatic vhydrocarbon radical of 1 to 7 carbon atoms or is R C0OX R is a divalent aliphatic or aromatic hydrocarbon radicalof 1 to 9 carbon atoms, which may 'be the same as or different from any other R X is hydrogen, alkali, metal, alkaline earth metal, other suitable salt-forming metal, ammonium, al-kylamine or alkanolamine, which may be the same as or different from any other X in the formula, m is from /3 to 1 and n is from 1 to 3, both m and n being dependent on the valence(s) of X. Usually, the aminocarv boxylate comprises from 3 to 30% of the composition and the inorganic builder is from to 70% thereof. Adjuvants may also be included, to contribute their special 1 properties.

Q Also within the invention are processes in which the I built synthetic organic detergent compositions mentioned 'above are employed as washing-softening agents in laundering textiles, clothing or other items, or in pre-soaking or' after-soa'king of such materials, to improve the 'softness oranti-static properties thereof. Such processes also include use, of the aminocarboxylate without the presence I of inorganic builder salt.

I n the formula given above it will be noted that the -dbsig'nations of m and it allow for the use of monovalent, ,1 divalent or trivalent atoms or radicals to form acids or salts,v that are utilized in this invention. In preferred compounds, X isv hydrogen, alkali metal, such as sodium or potassium, or other monovalent ion, preferably ammonium, alkyl amine or alkanolamine, and both m and n are I equal to 1., '-.[Preferred embodiments of the aminocarboxylates and aminocarboxylic acids employed are those of the formula "previously given wherein R is an aliphatic hydrocarbon 'radicalof 8 to 14 carbon atoms, R is an aliphatic hydrocarbon radical of 1 to 2 carbon atoms or is R COOX, R is a divalent aliphatic hydrocarbon radical of 1 to 3 carbon atoms, X is hydrogen or a monovalent salt-forming ion which is. either an alkali metal, ammonium, mono-, di- 'or tri-alkylamine, or mono-, dior tri-alkanolamine, and m and n are both equal to 1. In such compositions, it is preferred for both Xs and R s to be the same, if more than one should be present. The preferred compounds mentioned are found to be excellent textile softeners in .the compositions of this invention and in the processes thereof, especially for cotton articles washed with them, even after washing in the presence of the strong builders and other adjuvants and after normal rinsing. With respect to such properties, the most preferred compounds are the salts of N-(Z-hydroxy-higher alkyl)-N-methyl glycineN- oxides and the N-(Z-hydroxy-higher alkyl)-iminodiacetic acidN-oxides, wherein the higher alkyl is of 12 to 16 carbon atoms and is of straight chain structure. Of such compounds, it is preferred to employ the sodium and potassium salts, with the sodium salt being that which is most useful. Of the iminodiacetic acid compounds and the .N -methyl glycine compounds mentioned, the more effective inthese compositions and; processes for the softening of cotton textiles are the N-methyl glycine oxides. Although preferred and most preferred embodiments of the invention have been mentioned above, including the use of particular N-oxide aminocarboxylates and N-oxide-aminocarboxylic acids, other composition and methods within the scope of the present invention utilize other such .compounds within the scope of the invention and the formula previously given. Such other compounds may .possess useful properties as surfaces active agents, wetting agents, emulsifiers, detergents and anti-static agent, although they might not also produce to the same extent the extremely desirable softening activities shown by the most preferred compositions and methods, and could, in some cases, be considered to be ineffective in this respect.

Among compounds within the scope of the generic formula previously given, which are useful in the present compositions and processes, are

N-(Z-hydroxynbutyl)-N-butyl glycine-N-oxide, sodium salt;

N-(Z-hydroxy-n-octyl)-N-isopropyl glycine-N-oxide,

potassium salt;

N-(Z-hydroxy-dodecyl)-N-t-butyl glycine-N-oxide;

N-(Z-hydroxytetradecyl)-N-ethyl glycine-N-oxide,

- ammonium salt;

N-(Z-hydroxypropylene tetramer)-N-methyl glycine-N- oxid tri y amine salt;

N- Z-hydroxyhexadecyl) -N-ethyl glycine-N-oxide, tri- The alkyl groups of the N-(Z-hydroxyalkyl) portions of the above compounds, unless otherwise indicated, are the preferred straight chain groups, terminally joined to the nitrogen atom.

The above compounds are only illustrative of those of the formula previously given but other compounds within the scope of the formulas are also useful and in many cases possess properties superior to compounds specifically listed above. Thus, variations in the above specific formulas may be made wherein other mentioned groups are substituted for the groups shown. In some cases, additional non-interfering substituents may be employed, usually on the longer chain portions of the molecules, where they do not significantly afiect the proportions of the final product. Among such substituents may be mentioned amino, hydroxy, halogen, e.g., chlorine, bromine, fluorine,

and hydroxy-lower alkyl, wherein the alkyl is of up to 4 carbon atoms. Such substituents will usually be present in small number, generally no more than four being present on the molecule and usually less than three. Generally it is preferable that the compounds not be substittued but the substituted compounds are often of utility similar to thosewhich are literally within the formulas given. As illustrated in the recitations of specific compounds within the formulas, given above, mixed salts may be employed, as may be acid salts. The salt-forming metal or other radical, if divalent or polyvalent, may be joined to both acid portions of the imino compounds. Also, in the formation of the salts, a single salt-forming ion may be joined to two molecules of the acids of this invention.

Although the normal alkyl groups are preferred for R branched chain materials may also be used. Thus, the various alkyl groups formed from propylene may be employed, such as the propylene tetramer and pentamer, a preferred form of which is a mixture averaging 13 carbon atoms. Also, although saturated hydrocarbons are preferred, those which are unsaturated, to the extent of one or two double bonds per radical, may also function as R R usually is a short chain material, preferably unsubstituted, and is most preferably methyl. When such lower alkyl group is replaced by hydrogen, the product obtained does not have the desirable detersive and softening properties of the compoundsof this invention and is difiicult to manufacture. R is preferably a short chain alkylene, usually of l to 2 carbon atoms, but it has been found that-lon er chain alkylenes. and even divalent hydrocarbyl aromatic compounds make useful products. X, while it may be hydrogen, is preferably a salt-forming ion. This is so because the salt is usually more stable and freer flowing and the built detergent compositions of the present invention are usually alkaline. Of the salt-forming ions, those which are monovalent are preferred because of their generally greater water solubility, an important feature in the present compositions and processes. However, even in those cases wherein solubility might be low, the compositions of this invention may be employed in other polar media and may even be useful in aqueous media, usually by including therein a hydrotrope or cosolvent.

The novel compounds of this invention may be prepared by oxidation of the corresponding amine. Thus, the N-(Z-hydroxyalkyl)-aminocarboxylic acid or iminodicarboxylic acid or salt thereof may be treated with an oxidizing agent, such as hydrogen peroxide or ozone, prefer-- ably in aqueous solution, and the Water remaining after the reaction may be removed by any suitable technique, e.g., freeze drying. Usually, the reaction will be run in an aqueous solution of a soluble salt of the starting material and will be conducted by slowly admixing the oxidizing agent with the solution of salt at a temperature about .room temperature, with cooling to maintain such temperature or one slightly higher sometimes being desirable because of the exothermic reaction and generation of excess heat. Cooling will be most useful when there is present a high concentration of amine to be oxidized. Normally, the addition of the oxidizing agent will take place within a period of from 30 seconds to one hour, at a temperature of 15 to 50 C. The solution may be held for an additional 30 minutes to 18 hours at a temperature of 40 to 90 C., to decompose excess H but this can also be done with catalysts, such as platinum or palladium, or with reducing agents, such as sodium sulfite. The proportions of reactants employed are such that the oxidizing agent is initially present in excess. Such excess will usually be from 5% to 100% of the stoichiometric proportion, so as to aid in forcing the reaction and producing a 100% yield of the oxide. Of course, less than the stoichiometric proportion of oxidizing agent may be used, in which cases yields will suffer. It is normally not desirable to use less than 75% of the stoichiometric quantity of oxidizing agent, unless it is desired to make a mixture of theoxide or salt and the unoxidized aminocarboxylic acid or iminodicarboxylic acid or salt. Instead of utilizing the water soluble salt, a comparable reaction may be run with the acid, which may be solubilized by suitable solvents, e.g., ketones, such as acetone, methyl ethyl ketone. Also, the salts may be made by subsequent treatment of the acid oxides produced with alkaline material, e.g., NaOH, triethanolamine. The acid forms of the oxide may be produced by acidification of previously manufactured salts.

N-(Z-hydroxyalkyl)-substituted aminocarboxylic acid or the corresponding -iminodicarboxylic acid starting materials or salts may be made by reactions similar to those described in our co-pending applications entitled N-(2- Hydroxy-Higher Hydrocarbyl) N Lower Hydrocarbyl- Aminocarboxylates and N-(Z-Hydroxyhydrocarbyl) Iminodicarboxylates, filed on the same day as this application. In brief, such reactions are of the N-substituted aminocarboxylic acid with hydrocarbon-1,2-epoxide. Such reactions are usually conducted at an elevated temperature, often about the boiling point of the reaction mixtures, which may contain some water, and after the reaction has been completed, which may take from minutes to 5 hours, the reaction mix is cooled and water is removed by any suitable technique. Such removal may be by freeze drying, flash vaporization, evaporation or other method. To remove impurities, the product may be extracted with a solvent for these, e.g., acetone. If desired, it may recrystallized from alcohol. The starting epoxides and amino-carboxylic acids or salts are well-known compounds and methods for their manufacture are obvious.

In the preferred heavy duty synthetic detergent compositions of this invention the oxides of aminocarboxylates or oxides of aminocarboxylic acids are built with Water soluble builder salts. The builder salts are usually inorganic and most often are salts of alkali metals but suitable salts of other metals, such as alkaline earth metals, magnesium and aluminum, and non-metals and radicals, e.g., ammonium and organic cations, such as mono-, di-, and tri-alkylamines and alkanolamines wherein the alkyl and alkanol groups are of about 1 to 4 carbon atoms, preferably of 2 carbon atoms, are also useful. The builder salts are preferably phosphates, including orthophosphates, pyrophosphates and tripolyphosphates, but the usual builder silicates, borates, carbonates, or bicarbonates, may be used instead of or in conjunction with the phosphates. It will be noted that the builder salts are usually of alkaline pH in dilute solution and this also often increases the detergency of the built compound. However, in some circumstances it is desirable to maintain a lower pH and at such times more neutral builders, such as the alkali metal salts, both complete and partial, of sequestrants such as nitrilotriacetic acid or ethylene diamine tetraacetic acid may be employed. Examples of the builders that may be used include sodium tripolyphosphate, tetrapotassium pyrophosphate, pentapotassium tripolyphosphate, sodium pyrophosphate, sodium hexametaphosphate, sodium carbonate, potassium carbonate, sodium tetraborate, sodium silicate (Na O/SiO ratios of about 0.5 to 0.3), potassium bicarbonate, potassium sesquicarbonate, sodium sesquicarbonate, trisodium nitrilotriacetate, tetrasodium salt of ethylenediamine tetraacetic acid, and the sodium salt of methylene diphosphonic acid. In place of the specific compounds, the suitable corresponding alkaline earth metal, ammonium, lower alkanolamine or lower alkyl amine salts are also employable, either in complete or partial substitution therefor.

With the built detergent-softener compositions there may be included for additional effects other detergents and softening compounds. For example, although it is preferred to utilize anionic synthetic organic detergents, other detersive materials, such as compatible cationic, amphoteric and nonionic surface active agents and detergents may be used, too, in suitable formulations. The anionic compounds include higher alkane sulfonates, higher fatty acid monoglyceride sulfates, linear higher alkyl benzene sulfonates, higher fatty acid soaps, polyoxyethylene sulfates, hydroxyalkane sulfonates, higher al cohol sulfates, salts of lower alcohol esters of sulfofatty acids, aromatic polyethoxyether sulfates, acyl sarcosinates, acyl esters of isethionates, acyl N-methyl taurides and others of the commercially available well-known anionic surface active agents and detergents. In such compounds the aromatic group will usually be benzene, the polyethoxy group will usually be from 3 to 30 ethoxys or other lower alkoxys, the lower alkyl will normally be of 1 to 6 carbon atoms and the higher alkyl will be of 8 to 22 carbon atoms, preferably from 12 to 18. The salt-forming metals or other suitable radicals are preferably alkali metal, such as potassium and sodium, but alkaline earth metals, e.g., calcium, ammonium, lower alkyl amine, lower alkanolamine, and magnesium may also be employed. Specific examples of the anionic detergents include sodium lauryl sulfate; sodium linear tridecyl benzene sulfonate; triethanolamine lauryl sulfate; sodium and potassium coconut oil-tallow soaps; sodium lauryl sulfonate; potassium hexadecyl naphthalene sulfonate; lauryl alcohol ethylene oxide sulfate comprising 4 ethoxy groups per molecule; potassium stearyl glyceryl ether sulfonate; sodium lauroyl sarcosinate; and magnesium N-methyl tauride. These are only a few of the well-known anionic surface active agents and to those of skill in the art identification of other members of this class will be obvious.

Among the nonionic surface active agents are the condensation products of alkylated phenols with ethylene oxide, alkyl thiophenols with ethylene oxide, higher fatty alcohols with ethylene oxide and polyalkylene glycols or other polyols with lower alkylene oxides. Specific compounds within this class are phenols condensed with from 6 to 30 moles of ethylene oxide; condensation products of polymers of propylene oxide with polymers of ethylene oxide; and ethers from higher fatty alcohols, such as lauryl alcohol, and polyethylene oxide.

Representative of the cationic surface active agents that are usable are N-2-aminoethyl higher alkyl amines; N-2- aminoethyl higher fatty acid amides; quaternary ammonium compounds wherein an alkyl group is of about 12 to 18 carbon atoms and the other groups attached to the nitrogen are alkyls of 1 to 3 carbon atoms. Typical of the preferred quaternary ammonium detergents are ethyl dimethylstearyl ammonium chloride; benzyl dimethylstearyl ammonium chloride; trimethylstearyl ammonium chloride; and trimethylcetyl ammonium bromide. Of course, others of these well-known cationic detergents may be used instead. The quaternary surface active materials also function as softening agents.

The amphoteric detergents, which contain both anionic and cationic groups, include the N-higher alkyl betaines, N-alkyl-beta-aminopropionic acid; and N-alkyl-beta-iminodipropionic acid. It will be noted that these compounds bear a superficial resemblance to the softeners of the present compositions. Other suitable amphoteric detergents include the fatty imidazolines and betaines containing a sulfonic group instead of a carboxylic group.

To impart their particular effects to the material being treated, other adjuvants may also be employed in the present detergent compositions. These include filler salts; solvents; soil-suspending agents or anti-redeposition agents, such as sodium carboxymethyl cellulose and polyvinyl alcohol; perfumes; dyes; optical brighteners; antioxidants; preservants; hydrotropes, bactericides; anti-tarnish agents; opacifiers; bleaches; bluings; abrasives; enzymes; thickeners; foam-enhancing agents; foam-destructive agents; sequestrants; and various other adjuvants. Examples of such materials include 2,6-di-tertiary butylphenol (antioxidant); sodium 2-sulfo-4-(2-naphtho-1,2 triaz'ole) stilbene (an optical brightener); lower alkyl aryl sulfonates such as sodium toluene sulfonate, sodium cumene sulfonate and potassium xylene sulfonate (hydrotropes); trichlorocarbanilide and hexachlorophene (bactericides); sodium perborate and potassium dichloroisocyanurate (bleaches); pepsin, keratinase and papain (enzymes); water, ethanol, propylene glycol, isopropanol (solvents); sodium sulfate (anhydrous), Glaubers salt, potassium sulfate, sodium chloride, ammonium sulfate (filler salts); lauric diethanolamide (foam enhancer and thickener) and dimethyl siloxane (foam destroyer).

The detergent-softener compositions of this invention may be in either a solid or liquid form, including pastes, gels, free-flowing liquids, emulsions, lotions, thick liquids, bars, cakes, tablets, capsules, powders, granules, spraydried beads and other suitable forms. These may be produced by usual formulating and processing techniques. To make solids, it is possible merely to blend the various constituents of the desired composition and mix carefully. The powders resulting may be packaged in paperboard cartons or in water soluble polyvinyl alcohol packets. Alternatively, after mixing, these may be tabletted, milled, plodded and pressed, dried, agglomerated or subjected to other process steps. Usually, to make the liquid or gel forms of these compositions, the constituents are dissolved or suspended in a liquid medium, such as water or other suitable solvent, after which they may be treated to convert them to other suitable forms. In one case, a crutcher mix or solution of the N-oxide aminocarboxylate and a.

builder salt, either with or without adjuvants, is spraydried in a conventional spray tower to produced particles or beads instead of mechanically blended powder. The

filler salts, hydrotropes, other detergents and other'ad' juvants may be added after spray drying or, in suitable cases, may be blended in with the crutcher mix and dried with it. 1

If made into a liquid, it is preferred that it be a free flowing liquid, of a viscosity between that of water and a syrup, such as maple syrup. If produced as a powder, it is preferred that the particle sizes be from 6 mesh to, 200 mesh, preferably being from 12 mesh to 100 mesh (US Standard Sieve Series). However, as indicated previously, other physical forms of the product may be employed.

Whatever the form of the product, it is important that. it contain sufiicient of the detergent-softener compound to be effective in use. Thus, usually less than 2% of-s'uch material in a solid or liquid product is found to be so low a concentration that when utilized as an additive to wash water or rinse water in an automatic washing machine or when employed as a pre-soak, the concentration of active. materials in the final solution is such as to be comparatively ineffective. Therefore, it is considered to hemportant that at least 2% of the present active detergentsoftener be present in the compositions. Similarly, at least 5% of builder salt should be present to have its effect obtained. Maxima of such materials are considered to be 50% and 98%, respectively. Preferred ranges of propor tions of the active compound and builder salt, respectively, are 3 to 30% and 10 to 70% of the composition. If solid product is made, it will normally be most desirable to include from 10 to 20% of the active compound in it, together with 20 to 45% of a builder, such as pentasodium tripolyphosphate. Similarly, when solutions are marketed, they should contain from 5 to 20% of the active compound, 10 to 30% of builder salt, such as tetrapotassium pyrophosphate, and 35 to waterQAt such concentrations and with such materials, the detersive and softening effects are not adversely effected by the builder salt or other synthetic surface active agents or fillers. Rather, detergency is improved by the'builder and anti-static effects may often be noted on the washed textile. 1 1

Of course, other liquid or solid adjuvants may also be employed. This term includes other synthetic detergents, softeners, hydrotropes, solvents, fillers, etc., as well as other more minor additives. Generally, from 0.1 to 25 of an adjuvant may be included in the present composition, depending upon the nature thereof. A supplemental. synthetic detergent, surface active agent or filler salt may be used in comparatively large proportion, e.g., 10 to 25%, whereas a fluorescent dye or perfume will usually be present only to a very minor extent, e.g., 0.1 to 2%. Preferred-ranges for most of the various adjuvants are from 0.5 to 5% of each, with a total adjuvant content of no more than 50% of thecomposition. However, as, much as 50% inorganic filler salt can be used. Such salts,- including sodium sulfate, potassium sulfate, and sodium; chloride, are often added to aid in improving the physical properties of particulate solid compositions. of this inven-- tion. They may also be present as byproducts of reac-- tion or as fillers in the starting materials. A preferred. concentration thereof in the present products is from 5 to 35%. In cases where some adjuvants may be incom patible upon storage with other constituents of the present; compositions, their effects may be obtained by adding them to the wash water together with the present compositions. Except for those cases of incompatibility, the vari-' ous constituents of these compositions may be mixed] together at any suitable stage of manufacture, in some cases even being added during the chemical manufacturing process whereby the present amine oxides are produced. In such a situation, a synthetic detergent or hydro trope might be employed during the reaction of olefin oxide with amino acid to make the precursor of the pres ent compounds. The surface active material can then be carried over with the active ingredient and have its effects utilized in the final product, as well as in the manufacturing procedure. Thus, it is seen that variations in process ing conditions may be used. Processing temperatures may be from 20 C. to over 400 C. but are usually from room temperature to ordinary spray drying temperatures, such as 25 C. to 300 C.

In use, the present compositions are diluted with about to 100,000 parts of solvent, such as water, per part of the N-oxide aminocarboxylate detergent-softener compound, to make an effective softening solution. Preferably, the dilution will be with from about 500 to 25,000 parts and most preferably, with about 2,000 to 10,000 parts of water. On a product basis, adjustment will be made for the generally lesser proportion of active material in the liquid preparation but it can be said that usually there will be used from about 100 to 4,000 times as much water as composition. Generally, for a solid product, the amount of water employed will be from about 400 to 2,000 times the weight of the solid, whereas in the case of the liquid preparations, the ratio will be from about 200 to 1,000.

Textiles washable with the present compositions include those made from cotton, wool, rayon, nylon, polyesters, cellulose acetate, and other natural and synthetic fibers. Human and animal hair, including living hair, may be treated with the N-oxide aminocarboxylates, but usually the compositions for treating living hair will contain little or no alkaline builder salt.

The detergent-softener composition is normally added as the active detergent ingredient to an automatic washing machine before beginning of washing. It may provide the entire detergent and softening actions or it may be supplemented by other preparations for such purposes. In either case, by adding before the final rinse, it is possible to have a softened wash Without the necessity for special equipment on the automatic washing machine or the need for the housewife to keep watch over the machine so that she may add softener in the rinse. A similar effect may be obtained by using approximately the same proportions of detergent-softener composition as a pre-soak, before washing. Such presoaking may be combined with an enzyme treatment. If considered desirable under the circumstances, the compositions may be added to the rinse water, although this is not usually necessary to obtain the desired softening effect.

The present products have been found to be effective in both hard and soft waters and when washing at either high or low temperatures. Thus, they are useful detergentsofteners over a hardness range from soft water, e.g., 0f 0 to 50 p.p.m. hardness, to as much as 300 p.p.m. of hardness, calculated as calcium carbonate. Such hardness may be due to Ca++, Mg' or other hardness ions or mixtures of such ions in the water. The invented compositions are useful at washing temperatures ranging from 20 to 100 C. but most often the temperature of the Wash water is in the range from 30 to 70 C.

The builders employed in the present compositions are usually alkaline and therefore the wash water or soak or rinse water containing such compositions will usually be of pH in the range of 8 to 12, with the range from 9 to 11 being preferred. Nevertheless, it is possible to operate at other pHs with useful effect. In fact, a method of this invention for washing and softening textiles may also be followed in the absence of builder salt, in which case it is easy to obtain a lower pH, e.g., 4 to 7. Although it is most highly desirable to employ the N-oxides of N-(Z-hydroxy higher alkyl) aminocarboxylates in conjunction with inorganic builder salt, the present invented method extends to utilizing the active compounds alone or with adjuvants other than the builder salt. Thus, where only a softening eflfect or antistatic action is wanted or when material being treated is not badly soiled, so that detergent action is unnecessary, the amount of inorganic builder salt present may be diminished and even reduced to zero. The methods of use of such compositions, without builder salt, are the same as those previously described herein.

The soaking, washing and rinsing times employed are those ordinarily followed in treatments of textiles. Thus, soaking may be for a period from about 5 minutes to overnight, washing may take about 2 to 25 minutes and rinsing may take about 2 to 10 minutes, in the usual machine washing operation. Nevertheless, other times and other obvious modifications of the preceding conditions may be made within the invention.

To illustrate the invention the following examples are given. They are not to be interpreted as limiting the invention to the specific embodiments set forth herein, since it is clear that the working examples show only certain preferred embodiments of the invention. Where a single active compound or builder or other material is indicated in the examples or in the specification, it is clear that mixtures of the equivalent materials, within the invention may be employed instead. All temperatures are in degrees centigrade and all parts are by weight, unless otherwise noted.

EXAMPLE 1 Percent N-oxide of -N-(Z-hydroxytetradecyl)-N-methyl glycine, sodium salt 10.0 Potassium pyrophosphate 15.0 Sodium xylene sulfonate 8.0 Water 65.0 Other materials (impurities byproducts) 2.0

The above formula is compounded by mixing the various solid ingredients and dissolving in water, at approximately room temperature. The product resulting is a clear one-phase, low viscosity liquid. The N-oxide is made according to the method described in our application entitled N-oxide-Aminocarboxylates, filed together with this application. The other ingredients are commercial products or are present with such products.

140 grams of the liquid product /z cup) are employed in a test of detergency and softness, identified as the ltowel test. In this test, one white terrycloth hand towel ('16 inches by 26 inches), obtained from J. C. Penney C0., is Washed in a General Electric automatic washing machine of 17 gallon capacity. New Brunswick, NJ. tap water of about p.p.m. hardness is used, at -F. After air drying of the towel, it is rated for softness. The

scale employed is from 1 for no softness to 10 for excellent softness. Whiteness is evaluated visually and instrumentally, using a Gardner Color Dilference'Meter. Before testing, the towels are first washed (2 dozen per load) with ten grams of linear tridecyl benzene sulfonate and 40 grams of sodium tripolyphosphate to remove the mill-applied finish.

By this test, wherein the liquid detergent/softener is added in the washing step, a softness rating of 9 is obtained. In a similar experiment, wherein the oxide employed is that of N-(Z-hydroxydodecyl)-N-methyl glycine, sodium salt, the softness obtained is 10.

When the 10% of N-oxide employed is replaced by 5% thereof plus 10% of higher alkane sulfonate (C -C softness ratings of 9 result. When the 10% of N-oxide of N-(2-hydroxydodecyl)-N-methyl glycine, sodium salt is replaced with 5% of this compound and 10% of linear dodecyl benzene sulfonate, the softness rating is 7. In the above cases, the'extra material added represents water omitted from the formula. In the above formulas, detergency testing indcates effective detergency of the cotton towel in both hard and soft waters at both elevated and room temperatures. Also, when tested for static effects, such as cracking after machine drying, the cotton Eowels and others of rayon, nylon or polyester are staticree.

'Similar results are obtained when, instead of the N- oxide of N-(2-hydroxydodecyl)-N-methyl glycine, sodium salt, the hexadecyl homologue is used. Comparable results are obtained when, in place of the sodium salts mentioned herein, potassium or ammonium salts are used. Also, when the proportion of N-oxide present is varied from 3 to 30%, equally high ratings and superior ratings are obtained for the compositions including more than 10% and correspondingly, lesser softening effects are obtained with the 3% formula. Nevertheless, measurable and useful softening does result. When the octadecyl homologue is used in the same formulas, surprisingly enough, it is noted that the softening is less than with the dodecyl, tetradecyl and hexadecyl compounds.

When the builder salt is omitted, being replaced by sodium sulfate or water, softening effects are comparable with the mentioned N-oxides but detergency is diminished. Similarly, when the proportion of builder salt is decreased to 5%, detergency is lowered from the level of experimental formulas and when the proportion is raised to 50%, detergency and alkalinity are'substantially increased. However, in both such cases, softening and anti-static effects are satisfactory.

When the use concentration of the liquid composition is increased five fold, detergency and softening effects are improved while when it is diminished to 30 grams per tub full of water, detergency, softening and antistatic efl ects are all diminished measurably, but useful effects are still obtained.

EXAMPLE 2 Carbon content is superior to the other, with both being far superior to a control with linear tridecyl benzene sulfonate detergent, used to wash towels. The softness ratings are 8 and 6 respectively. g

It is noted that the softness observed is of a diiferent character from that obtained by rinse-treating textiles with quaternary ammonium halide softening agents. The latter compounds impart a somewhat greasy feel to the textile, which is not noted when the present compounds are employed in the manner described.

When the above compositions are used to treat a textile by pre-soaking in water containing 10 times the'above concentration of active softening composition of this invention, after overnight standing and subsequent Washing, rinsing and drying it is noted that the towel is significantly softer than a control towel not so pre-soaked or treated. Similar effects are noted when these compositions, with or without inorganic builder salt, are used to treat the towels in the rinse water, using the same washing machine and a usual washing cycle.

EXAMPLE 3 A powdered detergent-softening composition is made by blending together, in powder form, 15% of N-(Z-hydroxy higher alkyl)-N-methyl glycine-N-oxide salt, or N-(2-hydroxy higher alkyl) iminodiacetic acid-N-oxide salt with 35% pentasodium tripolyphosphate and sodium sulfate. The composition prepared is tested for detergency at 0.15% concentration. Four different active ingredients are included in these various formulations and the effects thereof are given below. The test employed to measure detergency is identified as the Spangler Soil Detergency Test. These tests are run using three cotton percale swatches, each three inches by six inches, each of which is soiled with Spangler Soil (mixture of airborne and sebum soils). Washing of the swatches is done in a Tergotometer evaluating washing machine. The washing is done at two hardnesses and at two temperatures, as indicated. Swatches are checked with a color dilference meter before and after washing, using the Rd scale. The difference in Rd, or delta Rd, is calculated and reported. The greater the delta Rd, the more eflicient the removal of soil and the better the detergency obtained. Linear tridecylbenzene sulfonate, sodium salt, is employed as a standard of comparison for detergency in thistest. The results are reported in Table 1.

TABLE 1.SPANGLER SOIL DETERGENCY TESTS ARd (Soil removal), 120 F. F. Composition tested (35% sodium trlpolyhposphate, 50% sodium sulfate and 15% C, D, E, or F) N.B. tap 300 p.p.m. N.B. tap 300 p.p.m.

(C) lfI-(2-hydroxydodecyl)Nmethyl glycine-N-oxide,

sodium S 14. 9 10. 0 12. 5 10. 7 (D) IjI-(2-hydroxytetradeeyl)N-methyl glycine-N oxide sodium 5 16. 0 11. 4 14. 2 12. 1 (E) 1 I(2-hydroxyhexadecyl)-N-methyl glycine-N-oxide,

sodium salt. 16. 1 12. 7 12. 9 11. 1 (F) N -(2-hydroxyhexadeeyl) nmnodracetic acid-N- oxide,

um salt 14. 3 10. 6 16. 7 10. 4

dl-sodi 10% of an N-oxide active ingredient made from the olefin epoxide identified as A is blended with the other constituents of the composition described in Example 1.

Subsequently, a similar composition is made, based on the N-oxide derived from the epoxidized olefin identified as B, above. The products are single phase, low viscosity liquids at room temperature. They are tested for softness in the same manner as described in Example 1. It is,

found that the composition based on active ingredient derived from epoxide A, having shorter carbonchains,

From the data of Table 1, it is apparent that the present compositions are useful as detergents. Comparative tests of detergency, against a standard linear tridecylbenzene sulfonate detergent, show that comparable detergency is obtained in hard water at a F. washing temperature 13 when other salts of the mentioned compounds are employed, such as the potassium, magnesium, triethanolamine, trimethylamine, diethanolamine and ammonium salts.

EXAMPLE 4 The softening effects of powdered detergent compositions of this invention are tested by making up several compositions comprising 2 parts of the amine oxide compound and 6.6 parts of sodiumtripolyphosphate. This free-flowing powder is used to wash one-half of a terrycloth hand towel in three gallons of New Brunswick, NJ. tap water (90 p.p.m. hardness), at 120 F. The washing is carried out, employing 8.6 grams of the composition and using a General Electric automatic washing machine with Minibasket attachment in the machine. In a similar manner, control softener formulations are employed and towels washed therewith are compared to those washed using the experimental compositions. The towels washed are 13 inches by 16 inches and are purchased from J. C. Penney Co. as 16 inch by 26 inch towels, which are cut in half for testing. Before testing, the new towels are washed, two dozen towels per wash load, in a standard General Electric automatic washer, not using the Minibasket, and employing a full amount of water in whiuh are dissolved 10 grams of linear sodium tridecylbenzene sulfonate active ingredient and 40 grams of sodium tripolyphosphate. This operation removes any finish applied at the mill, which might otherwise make the-result of the test inaccurate.

The softness of the towels washed by various compositions is rated on the scale of 1 to 10 with 1 indicating a towel which is not soft and 10 indicating excellent softness. Such ratings are made by comparison with control towels washed in detergents or softening agents of known characteristics. Results of this test are reported in Table 2.

TABLE 2 Softening effects Compositions tested (6,6 parts of sodium tripolyphosphate and 2 parts C, D, E, or F): Softness (C) N-(2-hydroxydodecyl)-N-methyl glycine- N-oxide, sodium salt 10 (D) N-(2-hydroxytetradecyl) N methyl glycine-N-oxide, sodium salt 10 (E) N (2 hydroxyhexadecyl)-N-methyl glycine-N-oxide, sodium salt 10+ (F) N (2 hydroxyhexadecyl) iminodiacetic acid-N-oxide, di-sodium salt 4 From the data in Table 2, it is apparent that the compositions described possess significant softening efilects, with the N-alkyl glycine compounds being most effective.

When, in place of the above salts, the corresponding potassium or ammonium salts are used and when there are used stoichiometrically equivalent proportions of other compounds in these compositions, such as oxides of N-(2- hydroxy-n-butyl)-N-n-propylamine-N-propionic acid, ptassium salt; N-(Z-hydroxy-n-decyl)-N-aminobenzoic acid, ammonium salt. N(2-hydroxyhexadecyl)-N-methylaminotoluic acid, triisopropylamine salt; N-(Z-hydroxydodecyl) N amyl-aminoacetic acid; N-(Z-hydroxy-nbutyl)-iminodipropionic acid, potassium salt; N-(Z-hydroxy-6-ethyl-n-hexadecyl)-iminoditoluic acid, ammonium salt; N-(Z-hydroxy-N-decyl)-imino-isopropyl-benzoic acid, triethanolamine salt; N (2 hydroxyoctadecyl)-iminoacetic-propionic acid, magnesium salt; and N-(Z-hydroxytetradecyl)-N-methyl .glycine, sodium salt, comparable results are obtained, with the imino compounds being good detergents but not being as useful as softening agents as the described glycine derivatives.

The present invention has been described in conjunction with descriptions of various embodiments and examples thereof. Clearly, the invention is not to be considered as limited to the examples, since to one of ordiwherein R is an alkyl radical of 4 to 20 carbon atoms, or alkenyl radical of 4 to 20 carbon atoms containing one or two ethylenic double bonds, R is alkyl of 1 to 7 carbon atoms or is R COOX R is alkylene or aromatic hydrocarbon radical of 1 to 9 carbon atoms, X is hydrogen, alkali metal, alkaline earth metal, ammonium, monoalkylamine, dialkylamine, trialkylamine, monoalkanolamine, dialkanolamine, or trialkanolamine, in which the alkyl and alkanol groups are of 1 to 4 carbon atoms, m is from /3 to 1 and n is from 1 to 3, and a water soluble neutral to alkaline inorganic salt builder for the compound, which increases the detergency thereof.

2. A composition according to claim 1 wherein, in the formula of the compound, m and n are both equal to 1, R is an aliphatic hydrocarbon radical of 8 to 14 carbon atoms, R is an aliphatic hydrocarbon radical of 1 to 2 carbon atoms or is R COOX, R is a divalent aliphatic hydrocarbon radical of 1 to 3 carbon atoms, both Xs, if a plurality is present, are the same and both R s, if a plurality is present, are the same, and the builder salt is an alkali metal phosphate, silicate, borate, carbonate or bicarbonate, or alkali metal salt of nitrilotriacetic acid, ethylene diamine tetra acetic acid or methylene diphosphonic acid.

' 3. A composition according to claim 2 which comprises from 2 to 50% of said compound and from 5 to 98% builder salt.

4. A composition according to claim 3 wherein said compound is 3 to 30% and the builder salt is from 10 to 70% of the composition.

5. A composition according to claim 4, in said compound of which R is a linear alkyl radical of 10 to 14 carbon atoms, R is methylene and X is alkali metal, and in which composition the builder salt is an alkali metal phosphate.

6. A composition according to claim 5, which is in particulate solid form and which comprises from 10 to 20% of said compound and from 25 to 45% pentasodium tripolyphosphate.

7. A composition according to claim 5, which is in liquid form and which comprises from 5 to 20% of said compound, 10 to 30% tetrapotassium pyrophosphate and from 35 to water.

8. A composition according to claim 6 wherein, in said compound, R is of about 14 carbon atoms, terminally joined to the rest of the compound, X is sodium and R is methyl.

9. A composition according to claim 7 wherein, in said compound, R is of about 14 carbon atoms, terminally joined to the rest of the compound, X is sodium and R is methyl.

10. A composition according to claim 6 wherein, said compound, R is of about 14 carbon atoms, terminally joined to the rest of the compound, X is sodium and R is R COOX.

11. A composition according to claim 7 wherein, in said compound R is of about 14 carbon atoms, terminally joined to the rest of the compound, X is sodium and R is R COOX.

12. A composition according to claim 3 further containing a compatible anionic, cationic, amphoteric or nonionic detergent.

13. A method of treating textiles which comprises contacting a textile with an aqueous solution of a compound of the formula wherein R is an alkyl radical of 4 to 20 carbon atoms, or alkenyl radical of 420 carbon atoms containing one or two ethylenic double bonds, R is alkyl of l to 7 carbon atoms or is R COOX R is alkylene or aromatic hydrocarbon of 1 to 9 carbon atoms, X is hydrogen, alkali metal, alkaline earth metal, ammonium monoalkylamine, trialkylamine, monoalkanolamine, dialkanolamine, or trialkanolamine, in which the alkyl and alkanol groups are of 1 to 4 carbon atoms, m is from ml and n is from 1 to 3, and a water soluble neutral to alkaline inorganic salt builder for the compound, which increases the detergency thereof.

14. A method according to claim 13 wherein, in the formula of the compound, m and n are both equal to 1, R is an aliphatic hydrocarbon radical of 8 to 14 carbon atoms, R is an aliphatic hydrocarbon radical of 1 to 2 carbon atoms or is R COOX, R is a divalent aliphatic hydrocarbon radical of 1 to 3 carbon atoms, both Xs, if a plurality is present, are the same and both R s, if a plurality is present, are the same, and the builder salt is an alkali metal phosphate, silicate, borate, carbonate or bicarbonate, or alkali metal salt of nitrilotriacetic acid, ethylene diamine tetra acetic acid or methylene diphosphonic acid.

15. A method according to claim 14, the composition of which comprises from 3 to 30% of the compound 16 part 'of compound to 500 to 25,000 parts of water and a pH of 9 to 10.

17. A method according to claim 16 wherein the application of the composition to the textile is in the washing step of an automatic washing machine operation and the textile is of either cotton, wool, rayon or synthetic ber.

. 18. A method according to claim 17 wherein the composition is initially in powder form, comprising 10 to 20% of a compound wherein R is of about 14 carbon atoms, terminally joined to the rest of the compound, and X is sodium and R is methyl, and 20 to of pentasodium tripolyphosphate.

19. A method according to claim 17 wherein the composition is initially in a liquid state, comprising from 5 to 20% of compound wherein R is of about 14 carbon atoms and termnally joined to the rest of the compound, X-is sodium and R is methyl, and 10 to 30% of tetrapotassium pyrophosphate.

20. A method according to claim 19 wherein the com position also includes a hydrotrope and an inorganic salt filler.

21. A method according to claim 15, the composition further containing a compatible anionic, cationic, amphoteric or nonionic detergent.

References Cited UNITED STATES PATENTS 2,159,967 5/1939 Engelmann 260-404 3,359,208 12/1967 Cahn et a1. 252-137 HERBERT B. GUYNN, Primary Examiner H. A. PI'I'LICK, Assistant Examiner US. Cl. X.R. 

